textproduct: Rapid City

KEY MESSAGES

- Above average temperatures will remain in the forecast. The hottest days will be Today and Saturday with highs in the mid to upper 90s.

- Elevated to near-critical fire weather conditions are expected through Saturday.

- Best chance for passing showers and thunderstorms is on Sunday.

UPDATE

Issued at 921 PM MDT Thu Sep 3 2026

Very poor overnight relative humidity recovery tonight (~25-40 percent), especially across northeastern Wyoming and the central and southern Black Hills. Currently, RH remains in the teens to low 20s across this area. While winds have diminished in NE WY and the Black Hills, near-critical conditions will persist overnight given the poor overnight recovery.

Have issued a new Red Flag Warning for all of NE WY fire weather zones into Butte County SD from 1100 MT through 2000 MT Friday. Relative humidity will fall into the single digits to mid teens and southerly winds will pick up after 1000-1100 with gusts 25 to 30 mph. Potential for critical conditions in the Spearfish/Sturgis and Rapid City foothills zones, but held off for now. May need to expand the RFW into these areas. While RH will be critical across the southern Black Hills and Fall River County, winds are expected to remain below RFW criteria.

DISCUSSION

(This Afternoon Through Wednesday) Issued at 1141 AM MDT Thu Sep 3 2026

Afternoon satellite imagery shows clear skies over the area and upstream. So tonight's forecast is looking clear with diminishing winds this evening.

Friday will be warmer than today with high temps well into the 90s. Winds will be gusty again so fire weather is a concern for the western counties. Hi res models, with support from global ensemble models, hint at some early morning to afternoon isolated rain and thundershowers in south central and central SD. These are not expected to be severe but strong gusty winds are likely with any of the stronger cells that develop.

For the weekend, afternoon highs will remain well above normal for early September. Saturday's highs will be hotter, topping out in the mid to upper 90s for the SD plains, low to mid 90s in NE WY. Sunday's highs will be in the upper 80s to mid 90s.

For now, precip chances on Saturday are mainly contained to the Black Hills and the area to the northeast. But Sunday and Monday, an upper level trough looks to swing over Montana and that trough could bring passing thunderstorms to the area. The SPC doesn't have a severe risk out for Sunday or Monday but machine learning severe weather models are hinting at a low end risk of severe weather centered over the Black Hills for those days. Stay plugged into the forecast through the weekend for updates.

Beyond Monday, low end chances for precip lingers in the forecast with a cooling temperature trend.

AVIATION

(For the 18Z TAFS Through 18Z Saturday) Issued At 1121 AM MDT Fri Sep 4 2026

Expect VFR conditions through the forecast period. Gusty south/southeast winds are expected across most of the area today, calming down some after sunset.

FIRE WEATHER

Issued At 1141 AM MDT Thu Sep 3 2026

Warmer and much drier air continues to move into northeastern WY and southwestern SD. A Red Flag Warning has been issued for today for parts of the western fire zones.

Temperatures will be hot tomorrow and Saturday with highs well into the 90s to near 100 degrees. Very low humidity is also expected to continue, dropping to near or below 15 percent in the afternoons across northeastern WY and portions of far western SD. And with southwesterly winds gusting upwards of 25 to 30 mph again tomorrow, the Red Flag Warning may need to be extended for some areas.

Saturday will have near critical conditions with the limiting factor, for now, being the winds. Winds look to be not as gusty but will update forecast if changes are needed.

UNR WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning until 8 PM MDT this evening for SDZ327. WY...Red Flag Warning until 8 PM MDT this evening for WYZ314>318.